The present invention relates to a projection plane color correction method of a projector, a projection plane color correction system of a projector and a program for projection plane color correction of a projector, and especially, to a projection plane color correction method of a projector, a projection plane color correction system of a projector and a program for projection plane color correction of a projector, which can realize good color reproduction in case that a color image is projected on a wall or the like having a color.
One example of a conventional projector with a correction circuit is described in JP-P1992-53374A “a projector with a correction circuit”. As shown in FIG. 4, in this conventional projector with a correction circuit, an image projected on a projection plane 8 from a projector 10 is read by an information detection section 11, and a correction circuit 12 conducts a white balance adjustment and a brightness adjustment. The image in which a color and brightness are adjusted is projected again by means of the projector 10 via a driver 13.
Since it is not at all herein how the white balance adjustment is conducted, it is not known how it is realized, and however, it is conjectured that, in the white balance (white balance) adjustment generally conducted in a television technology, intensity of three kinds of primary color light of red (R), green (G) and blue (B) is adjusted, and in case that white is tinted with yellow due to influence of the projection plane 8 for example, blue light is made m.sub.b times more than usual, and a white color is obtained on the projection plane when white light is projected.
In other words, when intensities of red, green and blue of original each pixel are R, G and B, correction such as an equation (1) is conducted, and color light having intensities of R′, G′ and B′ is projected. Here, mr, mg and mb are proportional coefficients.
                              (                                                                      R                  ′                                                                                                      G                  ′                                                                                                      B                  ′                                                              )                =                  (                                                                                          m                    r                                    ·                  R                                                                                                                          m                    g                                    ·                  G                                                                                                                          m                    b                                    ·                  B                                                              )                                    (        1        )            In this manner, white color is displayed in corrected color.
With regard to a task in the above-described and shown conventional method, only white color is a strict object of the correction, and only balance is approximately corrected for other colors in a color image. Accordingly, other than an exceptional case, correct color reproduction of a color image cannot be conducted.